The present invention generally relates to multimedia files with audio, video and textual data and in particular relates to optimizing font files for multimedia files.
Presentation of textual information can be an important part of the video viewing experience. Text information may be used to represent the movie title, chapter names, specific track data, as well as subtitles. Subtitles may be used for conveying the dialogue of a video presentation in different languages, to aid those with hearing impairments, poor listening comprehension, or to suit the viewer's current listening preferences and at times to present the director or even user commentary in environments where such information is available.
Typically, embedding textual information such as subtitles with audio and video data into multimedia files involves run-length-encoding bitmap images of the subtitle text information. The run-length encoding of bitmaps provides an efficient way of storing the information, and since bitmaps are a pictorial representation of the text rather than a textual representation, there are no additional requirements to render the subtitles, such as utilizing embedded or resident font files. However, despite its advantages, because the text information is stored as bitmaps, it adapts poorly to changes in image frame size and as a result cannot be scaled with acceptable visual results to multiple sizes. In addition to the problem with scalability, bitmap representations are not easily searchable as text, which is an attractive feature from the perspective of categorization, metadata and archival activities.
The use of the actual text with respect to a known alphabet of a particular language to represent the textual information, e.g., a title, chapter names, and/or a dialogue in a movie, is one alternative to using bitmaps to represent the information. Using text in a movie typically requires the encoding of the text in a commonly acceptable representation. ASCII and Unicode are two such representations, where ASCII is typically used for encoding European languages and allows a maximum of 256 symbols, and Unicode is used for representing over 100,000 characters and other symbols from a very comprehensive list of world languages.
The displaying of such text can be done through the use of a mixture of bitmap and non-bitmap image representations such as those stored in True Type Font files. However, the size of these representations may pose a problem especially when dynamically displayed or utilized with languages that utilize unique symbols to represent each individual word in their corresponding vocabularies.
Accordingly, there is a need to provide an optimized text generation and display system that overcomes the above-noted issues and/or additional problems in the art.